Background: Alcohol-related harm is pervasive among college students in the United States of America and Canada, where a third to half of undergraduates binge drink at least fortnightly. There have been no national studies outside North America. We estimated the prevalence of binge drinking, related harms, and individual risk factors among undergraduates in New Zealand. Methods: A web survey was completed by 2,548 undergraduates (63% response) at 5 of New Zealand’s 8 universities. Drinking patterns and alcohol-related problems in the preceding 4 weeks were measured. Drinking diaries for the preceding 7 days were completed. Multivariate analyses were used to identify individual risk factors. Results: A total of 81% of both women and men drank in the previous 4 weeks, 37% reported 1 or more binge episodes in the last week, 14% of women and 15% of men reported 2+ binge episodes in the last week, and 68% scored in the hazardous range (4+) on the AUDIT consumption subscale. A mean of 1.8 (95% confidence interval 1.4, 2.3) distinct alcohol-related risk behaviors or harmful consequences were reported, e.g., 33% had a blackout, 6% had unprotected sex, and 5% said they were physically aggressive toward someone, in the preceding 4 weeks. Drink-driving or being the passenger of a drink-driver in the last 4 weeks was reported by 9% of women and 11% of men. Risk factors for frequent binge drinking included: lower age, earlier age of drinking onset, monthly or more frequent binge drinking in high school, and living in a residential hall or a shared house (relative to living with parents). These correlates were similar to those identified in U.S. and Canadian studies. Conclusions: Strategies are needed to reduce the availability and promotion of alcohol on and around university campuses in New Zealand. Given the high prevalence of binge drinking in high school and its strong association with later binge drinking, strategies aimed at youth drinking are also a priority. In universities, high-risk drinkers should be identified and offered intervention early in their undergraduate careers.